The use of virtual reality (VR) simulation is a promising and relatively recent approach for evaluating driving capacity among persons with neurological compromise. VR simulation allows the presentation of interactive, "real world" driving scenarios that can be used to objectively assess driving capacity, in a safe but challenging manner;many systems are also financially accessible to clinicians. A handful of studies in rehabilitation, have begun to demonstrate the potential utility of this technology. Although new to the field of rehabilitation medicine, driving simulation has a moderate history of research in the transportation literature, which has focused on issues of fidelity, validity and in the development of advanced driving simulators for training, technology and crash avoidance research. Although both lines of research differ in their objectives, the findings from this literature have much to offer the rehabilitation application of VR driving simulation. For example, clinical VR driving simulators have predominantly relied on basic measures of driving performance that do not integrate the empirical evidence offered from the transportation literature. The overarching goal of this study is to use a multidisciplinary approach to combine findings from these two fields to develop a VR driving simulator that generates measures that are both clinically relevant and empirically based. To achieve this, the proposed project brings together both transportation and clinical expertise, which has compiled knowledge from previous work to identify new VR driving performance measures for the proposed study. The proposed work includes 1) Development Phase, for final programming and development of the VR driving simulator and the instrumented vehicle and 2) Research Phase, to validate the VR driving performance measures by comparing performance to on-road driving with an instrumented vehicle. Additionally, the study will examine the ability of the VR driving measures to discriminate driving performance of individuals with and without brain injury. These objectives will be achieved by testing individuals with traumatic brain injury (TBI) and matched healthy controls. All participants will receive a VR simulation and on-road driving session, which will include a baseline condition (standard, non-interrupted) condition and an experimental (driving while performing common activities, i.e. using a cell phone) condition. Second, all participants will be administered a VR challenge drive, where participants will be exposed to two hazardous driving scenarios. Analysis of concordance between measures of simulated and on- road, and to comparison of driving performance at both the group and individual level are planned.